NAME curl_getdate - Convert a date string to number of
seconds since January 1, 1970

SYNOPSIS #include <curl/curl.h>

time_t curl_getdate(char *datestring, time_t *now );

DESCRIPTION This function returns the number of seconds
since January 1st 1970 in the UTC time zone, for the date
and time that the datestring parameter specifies. The now
parameter is not used, pass a NULL there.

NOTE: This function was rewritten for the 7.12.2 release
and this docu- mentation covers the functionality of the new
one. The new one is not feature-complete with the old one,
but most of the formats supported by the new one was
supported by the old too.

PARSING DATES AND TIMES A "date" is a string
containing several items separated by whitespace. The order
of the items is immaterial. A date string may contain many
flavors of items:

calendar date items Can be specified several ways. Month
names can only be three- letter english abbreviations,
numbers can be zero-prefixed and the year may use 2 or 4
digits. Examples: 06 Nov 1994, 06-Nov-94 and Nov-94 6.

time of the day items This string specifies the time on
a given day. You must specify it with 6 digits with two
colons: HH:MM:SS. To not include the time in a date string,
will make the function assume 00:00:00. Example:
18:19:21.

time zone items Specifies international time zone. There
are a few acronyms supported, but in general you should
instead use the specific relative time compared to UTC.
Supported formats include: -1200, MST, +0100.

day of the week items Specifies a day of the week. Days
of the week may be spelled out in full (using english):
Sunday, Monday, etc or they may be abbreviated to their
first three letters. This is usu- ally not info that adds
anything.

pure numbers If a decimal number of the form YYYYMMDD
appears, then YYYY is read as the year, MM as the month
number and DD as the day of the month, for the specified
calendar date.

STANDARDS This parser was written to handle date formats
specified in RFC 822 (including the update in RFC 1123)
using time zone name or time zone delta and RFC 850
(obsoleted by RFC 1036) and ANSI Cs asctime() for- mat.
These formats are the only ones RFC2616 says HTTP
applications may use.

RETURN VALUE This function returns -1 when it fails to
parse the date string. Other- wise it returns the number of
seconds as described.

If the year is larger than 2037 on systems with 32 bit
time_t, this function will return 0x7fffffff (since that is
the largest possible signed 32 bit number).

Having a 64 bit time_t is not a guarantee that dates
beyond 03:14:07 UTC, January 19, 2038 will work fine. On
systems with a 64 bit time_t but with a crippled mktime(),
curl_getdate will return -1 in this case.

REWRITE The former version of this function was built
with yacc and was not only very large, it was also never
quite understood and it wasnt pos- sible to build with
non-GNU tools since only GNU Bison could make it
thread-safe!

The rewrite was done for 7.12.2. The new one is much
smaller and uses simpler code.